This work investigates the structural, magnetic and magneto-optical properties of a new zinc phosphate-tellurite glass belonging to the 45ZnO-10Al₂O₃-40P₂O₅-5TeO₂ system. The glass was prepared by a wet method of processing the starting reagents followed by suitable melting–stirring–quenching–annealing steps. Specific parameters such as density, average molecular mass, molar volume, oxygen packaging density, refractive index, molar refractivity, electronic polarizability, reflection loss, optical transmission, band gap and optical basicity have been reported together with thermal, magnetic and magneto-optical characteristics. Absorption bands appear in the blue and red visible region, while over 600 nm the glass becomes more transparent. FTIR and Raman spectra evidenced phosphate-tellurite vibration modes proving the P₂O₅ and TeO₂ network forming role. Magnetic measurements reveal the diamagnetic character of the Te-doped glass with an additional weak ferromagnetic signal, specific to diluted ferromagnetic oxides. Positive Faraday rotation angle with monotonous decreasing value at increasing wavelength was evidenced from magneto-optical measurements. The final product is a composite material comprising of a non-crystalline vitreous phase and Te-based nanoclusters accompanied by oxygen vacancies. The metallic-like Te colloids are responsible for the dark reddish color of the glass whereas the accompanying oxygen vacancies might be responsible for the weak ferromagnetic signal persisting up to room temperature.

The interest in ultrathin silver (Ag) films has increased due to their high surface plasmon resonance for coatings of only a few nm. Low roughness ultrathin films of 1 to 9 nm have been deposited on different substrates, such as polyethylene terephthalate (PET) and optical glass, using radio frequency (RF) magnetron sputtering. Films show good surface plasmon resonance up to 7 nm thickness, as revealed by the ultraviolet-visible (UV-Vis) spectra. The roughness of the films, investigated by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM), is small, and one can conclude that depositions are smooth and homogeneous. The bandgap values decrease with film thickness. The refractive index of the films, calculated from ellipsometry measurements, leads to values of under 1 visible domain, with minima in the wavelength range of 400–600 nm. The results are useful for obtaining lower roughness ultrathin Ag films with good surface plasmon resonance for photonic applications.

Mullite, 3Al₂O₃·2SiO₂, is a material with excellent thermal and mechanical properties. Two types of waste sand, rich in impurities, were employed as precursors for mullite ceramic synthesis. Two different synthesis routes were used: (i) solid-state reactions involving a sand and bauxite mixture, and (ii) precipitation synthesis, where alumina was deposited on sand particle surfaces; the sintering process was performed at temperatures ranging from 1300 °C to 1400 °C. Mullite was obtained as the main phase when the ceramics were obtained by solid-state reactions opposite to the second method, in which a composite ceramic with a specific microstructure, i.e., sand particles embedded in a matrix formed by alumina crystals, was assessed by electronic microscopy. The main properties, i.e., the apparent density, open porosity, compressive strength and thermal expansion coefficient (CTE) of the obtained materials were influenced by the composition and microstructure as well as the sintering temperature. The ceramics in which mullite was the main phase had slightly lower CTE’s and did not exhibit any phase transition in the 20–900 °C range. The results presented in this article highlight the importance of the synthesis route correlated with the nature of the precursors, the type and amount of impurities and the sintering temperature.